This paper identifies data modelling and data access and sharing requirements which multimedia applications impose on a database system. it shows the capabilities of an object-based data model and indicates extensions which are needed to meet the data modelling aspects of these requirements A logical implementation of the operations on the model is described the model generalizes the notions of instantiation and generalization in the standard object-oriented paradigm, and augments it with the notions of aggregation and relationship which are specialized for a multimedia application environment objects may exist in aggregation hierarchies which provide the capability to integrate diverse types of multimedia information such as text, sound bit-mapped Images and complex graphics drawings objects may also be linked through other user-defined relationship to capture such application functions as voice annotation and referencing of one document by another using this model the semantics of aggregation and relationship in a multimedia application environments can be understood and efficiently supported by a database system.